One example of a conventional LED light source for plant cultivation which can be used in plant factories etc. is a plant elongating apparatus disclosed in Patent Literature 1.
As shown in FIG. 11, a plant elongating apparatus 100 disclosed in Patent Literature 1 includes (i) a light emitting section 110 for emitting light for elongating plants, (ii) a power supply section 120 for supplying electricity to the light emitting section 110 such that a spectrum of light to be emitted is changeable, (iii) a determination section 131 for determining the type of a plant 101 to be cultivated, and (iv) a light spectrum setting section 132 for setting the spectrum of light by controlling the power supply section 120 according to the type of the plant 101 determined by the determination section 131.
The light emitting section 110 is (i) constituted by a large number of LEDs 112 arranged on one surface of a flat substrate 111, which LEDs 112 are of a plurality of types that emit light of different spectra, and (ii) arranged such that light emitted from the LEDs 112 is directed to the plant 101. Each of the LEDs 112 has a shape of a bullet, for example.
Another example of a conventional LED light source for plant cultivation is an LED light source for plant cultivation which is disclosed in Patent Literature 2.
An LED light source 200 for plant cultivation disclosed in Patent Literature 2 can be attached to a cover of a plant cultivation container, and is constituted by, as shown in FIG. 12, (i) a cathode terminal 201, (ii) an anode terminal 202, (iii) a light emitting chip 203, and (iv) an epoxy resin lens 204. The LED light source 200 for plant cultivation emits light 205 that has a color corresponding to the type of the light emitting chip 203.